From the above results, it can be seen that red mud addition up to 20%has enhancedthe reaction and properties. It is interesting to note that maximum peak intensity (Fig. 3), structural rearrangement (Fig. 4) and compressive strength (Fig. 6) was obtained in FARM10 samples which is due to optimum NaOH concentration and availability of Al and Si ions for reaction. The strength developmentcanbeattributed to the formation of compact microstructure due to enhanced dissolution and structural rearrangement (Fig. 7b). Elemental mapping of geopolymer with red mud showed that the Fe is embedded in the matrix of alumino-silicate gel. This is in agreement of earlier study where Fe was reported to be present in octahedral sites, either as isolated ions in dilute samples or as oxy-hydroxide aggregates in samples richer in Fe [44].